Baking oven



April 2, 1946. Y J. v. cooK V 2,397,725

' 'BAKNG OVEN Filed April 14, 1943 '7 sheets-sheet 2 A 2, 1946- .1. Vscook BAKINGOVEN- Filed Apri; 14, 1945 A 2, 194s. J. v. COOK 2,397,726

` BAKING OVEN Filled April 14, 1543 7 sheets-sheet 4 April 2, 1946. J. v. cooK BAKING OVEN Filed April 14, 1945 .f 2. ,w w w mf MV a .M l 2&5 7 7 7 fm@ f- L J A QM.. Nm;

April 2, 1946.l J. v. COOK 2,397,726

i BAKINGy OVEN Filed April 14., 1943 7 sheets-sheet 6 J. V. COOK BAKING OVEN April 2, 1946.`

Filedl April 14, 1943 '7 Sheets-Sheet 7 Patented Apr. 2, 1946 i UNITEo :lohn v. Conk,'vvi1mette, 111;, assign-0r to "r11-e- PetersenOven-fCompany, Chica 'poratiomof Illinois-- 4.YApplicaation Agnrilalvi,

- 9 laixn's.`

.The present:inventionwrelateseto .commercial typesiof bakingfoyens; :More partieularly,this,-invention Nis'fgdireetedto :baking yovenszzof1th e.lowA height type,l Limzludzing Acanhorizontally-trameling-g endless chain conveyer positioned within fthe bakiugmhamberlof :theoovenfte: :permit 1 loading of the; :conveyertuzoneaendt The .conveyemin suohovenifstmmtures isfsuohthat .the-foodstuff to.,be;baked;` is; :caused gto travel substantially around dane aconveyer, iny agsingle foourse, gdurina whichtime joakingzoperationtakes placay At the endof the :course mfitravel of athebaked `food stuit;- the:pansacontaining4 the-'same mftyibemanualhrmnloaded-fbut preferably; asrherei-n ,-showm aref.;` :discharged if onA oto' .an :unloading :conveyer which serves tofzeonveylthetbaked food stuiisrzexten'oriy ofrthe no3/exit` :Iheaconveyer asemployed in. :ovens oir this ztypeqdesirazbly. although V; not necessarily,- A:includes f :ga ,imultiplieity;.4 of t spaced apart trays, 'p vo-ta-l1yfA mounted atwopposite ends on .atpairrnfispaeedxstrands oi2endlessrohain.y

To insure proper? transfer; :of .--thefbaked :,iood stuffs :onto ztheunloadingfonvexer, the ,baking conveyer is preferably driven intermittentlyyand moves insa:stepfby-stepiashionzra; distanoereguivalenttozthe spacing between adjacent `traysf g sok as'daozcause-temporaryiarrestingfof the .ztraysfadnringfgthezdischarge for, transfer operation, :and fat the same ,tirrieicausing:aneemptzv;tray;4 to -be =dis. nosed..;in registrationv with itheiload-ingiopening atztheifrontferrdiotmhoven; n

It fisalalsoz pneflerred.^ thatA the unloading; icon- .Weyer he :driven in:.correlation Vto tthefhakim;Yeon-J vexitsso that isaid tunloadinggonveyeris inter# mittently-driven in conrespondenoe twithfzthefbaking conveyer, which permitsf-theprnpldisnharge ofdshea baked fogod :stuffs :from ztheahakingg; Ycom veyier'zonto the unloadingfconweyer, tand enables thesseparate: pansfvof .:food ,stuffs rtoixassume- :a proper :position-:omtheftunloading com/.ever for movement f tl'lereby.-A

Imthesluseo chamztypes of:balningfieonveyers,A vibration inherent :inzthe l-'movement fof-. thel :conveyerchain;givesa'great;concernto-:the' bakers be; cause: tofritheljigglingf zanzdiswinging; .motion im@ parted to the pivotedvtrayswduringg.movement .thereof,y and particularlvfduring thezamovement Yofzthe traysifrom onsfhorizonta'l run voffthlecon- ,veyersttoztheeothen Furthermore; ithis :condition lis f frequentlyzag,- gravated -zby dmproperl-positioning-v:of -ft-hepans :of ,food studs .on the trayswhioh resultstin .thekpans fregizentlwshifting ,'towardione end orone. side .ofthez-tray-,f.andioften oauseszthe body oftfood stuft-to ,ishifttoward one :endor fone side of the 59am,v thusfiresulting pin :non-tuniformity of .shape, thickness, vand. coloring, -or fbrowning Loftfthe baked food stuff. v

, Que-Soi the fobiectsmf ithelin-vention fis .-,to ,.pro-

vide-sa novelsa-fetyfdoor fnonstruetionf; lonatedat f go, Ill., a, oor- 1943Seia.l-fNo.482,976 Y 015107-580 thegfront ,lendr-of :the oven,L adjacentathegloading zonefof theoperatortandzwherein tthetsaietzv;door

is adapted tobermoyedto anopen.position Awheny the pans of :bakedtfood stnfffare dischargedffrom thema-king conveyer vand become jammedon they loading` fconveyer.

fAnother. .object .is to rprovidedav novel form tofdumping mechanism for oausingwtiltingi the pivoted ,trays-,onthelower runrof the bakingioonveyer, when .theo-latter .is arrested, f-for iconven ientlytdischarging ethepans of wfoodstuff on tothe unloading eonveyer.v

,-.lLfurtherfI .object isfto.. p rovidela.nm'el .defiecton chute-toonstrfucted landarrangedfor guiding,and directing.V the pans `of ifoodfstuii from @theA ,trays of Ythe.lo'ak-i.n graeonveiner `-.ontothe.\unloadingicon veye-r.

.Still anotheryfobjectj-s sto iprovide amoveltand improved bakingeonvever nonstrtuetion Y ,which results in substantially eliminatinglllswingking and -ijiggling motion of the :trayslduring: their course ofttravelqaroundlthe conveyer, and,.where in fthettrays. .are lmstrainecl in a ,predetermined Y upright position of adjustmentlthronghout.their entire course of Ytravel Aaround ,the conveyor.

Aistill further:objeettresidesin thefprovisio'n of. a `novel form of stabilizing l,means inthemature of avthree-pointsuspension iortgniding and sup? porting; fthe riveted. trays fin .lalsubstantiallymoricourse of travel around the eonveyer.

4And still aA further object ;is.,.tonrovideenovel guideV tracks for. one end of fthe .baking lsonvester for {guidi-ng themchainswof the .conveyeriand pref determi-ning .the ,path `of travel ,oithetrays .'with respect tothe loading' openingfat r`the ;fr ont, erid of the-loven.

.Otherflobjeets and .,advaritages.. of this nvenf tion willbeapparent fromttheofollo wing.descr-ip, 40 ton=,.v.taken in-.connection.With-; theccornpanying drawingsdn which:

fligure,y ,1- Lisa-,longitudina-l .sectontthrolighA-.the baking?- oven .embodying the pres.entimzer1tiori,.V taken adjacent the near side Wall of thermen, substantiallyzfas indicated at line ..I| of Eigu-re-.N13.-

rIign-re; 2 is .a wertiealttransversefsectional View through the -forwardTend; :of vthe baking. .oven,. rtaker-1:onalineZ-Loi-Iiigtuse 1, .showinglthe f-ramf in g-anddrivi-ngfarrangement nof .the unloading, convener: fanditsmelation,me thedoakinggfmien @when Y, Y v

-tEigure .3 fis .afi/er tical .transversesection-through d .the-:driving mechanism r of the..imloadingE conf-, '05 Veyer, taken substantialiy-ws findioateda-oniline 3.-.3..of.Fig1ure 2.: f

Figureei isaffragmentasy ser:tier-:salaries:` through theetaitend of theeunloadingteoneyer:.takemsnbf stantiaifly as'indieatedfonflinefi-- iofFignrenll. '60 l, r'ifnirey-istaztramngersetseationairivietn!thrnligh zontal `.I ipright @position throughout their...entire the novel safety door structure, at the forward end of the oven, takenv substantially as indicated v I at line -5on Figure 6. Y

Figure 6 is a fragmentary front elevational view of the oven, showingr the safety door construction in elevation.

Figure '7 is an enlarged vertical sectional viewY dicated at line 1.--1 of Figure 6. Y Y

Figure 8 is a fragmentary horizontal sectional view through the baking chamber, showing one 1 of the supporting trays and its connection to the conveyer chains supported on tracks within'the i ovenchamber.

" Figure 9 isV a viewv taken as indicated on line Figurev 10is anv enlarged sectional view through i one end of one of the trays and the stabilizing means associated therewith, and with the conveyer chain, taken substantially as indicated on through the safety door construction at the for?` ward end of the oven, taken substantially as in- 84-9 of Figure Sshowingone of the trays, partly in endelevation and partly in section. Y

'Figure V11 is a vertical sectional view through the head end of the baking conveyer, taken substantiauy as indicated on une A| of Figure 1.

Figure' 12 is a fragmentary vertical, longitudinal sectional view through the baking oven, taken as indicated on line I2-I2 on Figure 13, showing the loading end of the baking conveyer. Figure 13 is a transverse horizontal sectional View through the baking chamber, with portions broken away, showing both head and tail ends of lthe supporting and guiding track arrangements for the chains of the conveyer.

Figure 14 is a staggered view, part in section and part in elevation, showing the nove1 dumpl ing mechanism and discharge chute, embodyingv the presentinvention. Y

Figure 15 is a fragmentary view of a portion of the dumping mechanism, shown in aposition with end guide tracks 23 secured to the side Walls of the oven. The respective guide tracks connect the upper and lower. runs of thezrespective sets of supporting tracks 2l! and ,2|.2 Each of the guide tracks 23, as may be seen" in Figures 1 and 12 of the drawings, includes a curved A'section 23a merging with the upper horizontal track and a curved section 23h merging with the lower track. Said section 23o is disposed forwardly with respect to the upper curved section "23a, and I, theytwo curved sections are joined together by a straight upwardly inclined section 23o. The purpose of this novel end track design will hereafter be referred to.

The opposite ends of the horizontal tracks 2t and 2I are disposed in proper relation to the sprocket Wheels I'I, so as toV provideY a smooth and` continuous motion to the conveyer-.chains in their travel from one horizontal run to the other.

Mounted between the respective strandsof y chain I5, in longitudnial spaced apartrelation thereto, are a multiplicity of supporting trays, indicated generally at 25. These trays as may be seen in Figure 8 of the drawings are of the grille type, and include upright end walls 26 and 21. These trays are pivotally mounted "with re.l spect to the strands of chain I5, in an off-center relation-so that they tend to normally tilt in a rearward direction, as may be clearly seen in Figures 8 and 9. Suitable-means are provided for properly supporting the trays in a predetermined horizontal or upright position throughout'their entire path of travel around thefconveyer and which permits the trays to' be tilted in opposite direction by dumping mechanism, to be hereafter described, for theV purpose of discharging the load, comprising pans of food stuffs carried by the trays.

Each of the. trays includes inaddition to theV end walls Y2li Vand 2'I,A a multiplicity of spaced apart rods 29, welded to transversely extending tie rods 30 which in turn are welded on top of tubular members or pipes indicated at 3I.Y

end with a loading opening I2, adapted to be closed by a door I4, which may be understood to be movable in an upwardly direction to full open position, and which, for convenience, may be counterweighted in a conventional manner not shown. V

The baking conveyer extends horizontally in the baking chamber II and includes a pair of spaced apart strands of endless chain I5 of conventional bar link roller type. -These chains, at the far end of the oven chamber, aretrained around.v a pair of transversely spaced apart, axially aligned, driving sprocket wheels f I'I mounted on a horizontal shaft I8, one of which, it is to be understood, projects through the side wall of the oven and isconnected to suitable driving mechanism not shown.

The strands of endless chain provide upper and lower horizontal runs, supported upon two vertically spaced apart sets of` angle iron tracks 2D' and' 2l, which Ymerge and register, at the Yiorwardy orfloading lend of Y` the Vbaking chamber,

The Vsupporting surface of the tray isr thus'in the nature of a grilleA and permits free passage of the'heating currents upwardly' through'the l tray and around the pans of the food stuif to be baked for insuring a uniform ,baking operation during the course of travel of the food stuffsV around the baking conveyer. Y

The means for maintaining the trays 25 in a predetermined upright position of adjustment throughout their entire course of travel ,around the conveyer includes an endless strand of -bar link roller chain indicated at 32, which is disposed adjacent and infparallel relationto one ,ofi the strands of the conveyer chain I5, as seen in Figure 8 of the drawings, and is positioned for movement and support on the horizontal tracks 2| as seen in the drawings..V Y

At the drive end Vof therconveyer the auxiliary strand of chain 32 is mounted -for guided movement around a curved end guide track 34 secured to the same side wall of the oven chamber to which the horizontal tracks2l are connected, and as seen in Figures 1 and 11. YIt will be noted that the curved track B'is offset rearwardly and outwardly with respect to the adjacent sprocket wheel I'I. At 'the opposite or loading end of the conveyer the auxiliary strand of chain 32 is mounted for guided movement around an end guide track 36, connectedto the near wall of the oven chamber and which is of similar contour to the guide tracksl 23, Vbut 'spaced forwardly there'- @netgear from'fas may lclearlyseen inEi'gure jl for the drawings.

"Ihek trays 25 #are ipivotallyfmounted"G'on-trunnions at opposite ends thereof, providing journal support with "respect to the strands .of fchain' .I 5;' The endfZS #of fthe .ftrayg opposite lthe fiauxiliary strandof- Vchain-32; -is provided iwith'ra dixedfboss 40 'itofwhich is ri illy-attached@'trunnionpin -4 I., journaled fin aligned openings yprovidedfin 'a pair off-alignedlbar-i links hof the adjacent `Estrand "or chain l|-5,`'as seen in':1i"gure 8.

-At the-opposite' endV of ythe ltray, :adjacent `the auxiliary V"strand-cf :chain 232, therezis .provided aftrunnion24'3,ifrigidlyfattached'zas by welding to :a mounting `plate y'44,1of .generaliyisrectanigularcom toun--a's-seen in .Figu'reilgj .and "whichmlateis adapted to f'be .rigidly 'securedto the outer 'surface ofthe end wall 21 of the tray by means ofiscrews 452 'Theftiin'n'lonl 13 is adaptedltobe journal'ed in-v ontrl `.member indicated generally at Vlill whic includes spaced.Zapart,frearwardlyfextend irgaiixns M8 and f4`9,'f`dis'1osed-in` Substantiallyithe sainei horizon-'tal ip'lanesi .The :Satin 4491 is frigidly conneetedfasfby welding', to1a=sleevex51l ,journaledlbn the t1umnionf4'3','v sai-dfsl'eeve 2in1-` turn Sb'eing journaled' inf .faf'bushin'gf'il extending. through alligned-.openlngs'the --side fbars `4or #the endless chain f;|5` sfseen iniFigure 1101er `the drawings.

VThe-inrui-ll'fis' rigidiy'1conxiected-toithe inner enllflof fthe-sleeve 50fbylmeans aora lkey, 53, vand saldlfa'rin asic'learlyfseen inf Figure 9er the' kdraw-- ings' includes aliub vJp'ortiori: surrounding .thesleeve and lwhihinf turn xislloiilu'rcatedfso asfto provide :a clamping :action around I-Lthe :sleeve `by "means of alscrewll This arrangement permitsuuick and easyfassembly or-disassem'bly'of the parts so :asito fadilita't removal rand'replacement of oneofthe trayslz fwlienlioccasion .fnecessitates.4 f `If .desired thltrunnion'i andn'io'lmting lplat'e fMm'ay be made-fai part-of fea'chiti-'ay f or f'm'ay be removed inciderit "tof replacement' oflfatrayi.

The outer or rearward end of the arm 49lh'as rigidly? acoxmected 'Lth'ereto fia .laterally and `:outwardly-@'eatending tnunnion `Lor :pin B0 frwhicn 'in turnolsgjournaled in yafp'air of :alignedopenings in aepairaif zbartlinks Y'ci the :auxiliary'stran'dor ichain {lL-Was seeneiniliigure .;10.of .th'egdrawingsf at wniznowfbe apparent that -beeause :meauxiliary strand of chain 32 isrsupported :onthetsame lhorizontal `tracks 1.21 as thezadiacent v.strandof f,

chain :l5-;. and 'because' the :arms :'481and1'4911in effect becomezraasingle unitaryfstmlcture, they remain inilthevsamefrrelation.toxzthe .connected 'strands `of chain `at :all ,timesf except when @moving ifrorn one vofftheffhorizontal runs offtl-ie "conveyer'to the truiy; horizont-a1rdireetienatnus the adjustment of each trayfinfa true horizontal.planecantimainev tai-ns litin-'such` relation .througheutf-tlre entire course of travel around the conveyer. Thusithe food! stuff inlipans supported" on'the :tray 'dorn'ot becomedistorted .in'zshape .for :in thickness; which would. be` objectionable, particularly.. .when food Jst'ui is in the` nature v:of fcakes, :.pies :and :the like.

As may be seenfinL-riigure lro'f thedrawingsf-.the baking conveyeritravels in the direction indicated byzthe arrow, andbecausethe auxiliarystnandtof chain 32 fis trained'aroundsthe f curved endguide 3d at :the .driving7 .end tcf4 the 4conVeyerQ-the trunnion of the 1con'trol` memberfdl .is maintained in proper "cooperative horizontally aligned ...relation :to the ytrunnion 43, .sothat the traylmoves from Athe upper run ftothe lowenrunfottheicone veyer in'ia etrue'horizontal position, the .sa-meas the position .assumed when travelingralongffeither the'upper or lower/runs loftthe conveyer.' Likewise atthe loadingcf thesconveyer theend guidestrack 36 similarly controlstheposition ofthetrunnion S0, as the 'auxiliary ychain'spasses therearound to maintain the trayfin ntrue-horizontal plane as Ait moves lfrom the lower run-to the upper run=of theA conveyer.

Disposed .below `the'loadi'ng end :of 'the Abaking conveyer is a transversely' extending-'unloading conveyer of conventional form, one end of which projects through anfopeningL-,BG inthe -side wall of the oven as seen Vin Figure 2 of the drawinga The unloading conveyer yincludes suitable angle iron Supporting structures kindicated generally at '6.1. The driving l"end: oisaid funloadingccnveyer, located .outside rof lthe foven, asseen in Figure 2 of the drawings, includes aA pair^ of aligned drvingsprocketwheels 68, mountedvon a horizontal shaft A`69, journaled in `bearingswill carried by the `.framing structure-Bf". Thel outer end "ofthe Shaft 691s providedwithra sprocket wheel `'12, .driven Vby a chain 13,` from a sprocket wheel M associated Awith a speed reducer, 15, which in turn is driven by an electric .motor 7B; The opposite end vof hthe conveyer includes a spair of spaced apart arcuate guidetracks 18.\vhich merge with the/ends of angle iron rails ortracks and 8f! which serve tosupport the upperand lower runs of two spaced .apart strandsofbar link roller .chain 83, which are connected tol gether by inverted channellshapedsl'ats.'8`to constitute a substantially/,continuous weber Lap.- ron.

' The outer or :driving end of theunloadingconveyer may be connected'to any other `suitable apparatus for receiving the 4baked food 'stufflfrom the baking oven, .and as shown in dotted'outli'ne in Figure 2 the'unloading convey'er discharges onto a gravity-'red conveyer, a vportion'o which isiridicat'edflridotted'lii'ies at'i. L

'Mounted in the .lower'portion of 'the baking chamber' l'l is suitable heat exchange'm'eans in-` dicated generally at' 90,v including' a"niultipli'city of longitudinally "extending transversely spaced aparttube's' 9|, connected" at Vopposite' ends'to headersv "92 and 93. The headeVSTiS-disposeii intermediate' 'the upper 'and lower *runs of the unloadingfccnveyer', lasv clearlyf'seen in liiigure-i of the drawings; VBy :virtue 'of thisv arrangement it is Apossible to maintain* a---mininium"overall height of the baking oven in an oven structure vey'er 'for delivering 'the baked'ffod stuislto fthe exteriorfo'f the oven.- 'Thefheat transfer means may-obtain"itssupplyV4 df -*'heatf'fifom any sui-table source in #a conventionalinanner" 'Sand -lmay Voven into the baking chamber.

convenience, be. located in the chamber designated generallyat 95, located at the rear end is provided and, as may be noted in Figure l, the dumping mechanism is located for operation upon the trays on the lower run of the conveyer,`

adjacent the unloading conveyer. The dumping. mechanism includes a tray engaging arm normally disposed immediately' below the plane of the bottom of the tray as seen in Figures 1 and 14. YSaid arm is disposed to one side of the baking chamber in a, path adapted to be traversed by the outer end portion of the trays 25 as clearly seen in Figure 16. Said arm |95 is rigidly attached to the end of a-hcrizo'ntally extending portion lill, of a'crank-like shaft |92, which is journaled in bearings HB3, on platform |04, on the outside of the oven'proper. As may be seen in-Figure 16, the horizontal portion |B| of the shaft projects through the side wall of the Rigidly connected to the opposite or outer end of the crank shaft |92 is an arm I'i, the outer end of lwhich is pivotally connected to a connecting rod it, the lower end 'ofiwhich rod is pivotally'connected at |09 toa crank wheel llt, which wheel in turn is rigidly connected ,to a shaft associated with a speed` reducer VH2, driven byan electricr motor H3.

All of the operating mechanism here described is located outside theoven chamber and may be enclosed in a suitable sheet metalI housing, not shown. It is to be understood that the operating mechanism for the connecting rod |08 is constructed and arranged so as to move in a single cycle of operation and thenbecome temporarily arrested. During suchsingle cycle of movement, the crank wheel IE) moves from the initial position seen inFigure 14 and when it has traveled 180 from said position, the connecting rod |68 is disposed in the position seen in Figure 'l5 of the drawings. During the interim of movement from the initial position to the position seen in Figure 15, the tilting arm |90 engages the rearward pipe 3| of the tray 25 and tilts the tray about the axis of its trunnions and 43, and the tray acquires its maximum tilt at such position of adjustment of the rod |68.

It is to beunderstood that the baking conveyer is intermittently operatedl as aboveY described, and moves in a step-by-step manner, each step being equivalent to the spacing between adjacent trays. When the baking conveyer is arrested, it is to be understood that one of thetrays is arrested in registration with the dumping mechanism, with its trunnion axes substantially in registration with the axis ofthe upper portion of the crank shaft |82 of the dumping mechanisin. Whenthe tray is in itsfully tilted position, as indicated in dot and dash outline in Fig- Y ure l5, it is disposed with its load supporting surface at a sufficiently inclined rangle to cause `the pans of food stuffV normally supported on the rod |08, and the rod |8ris provided with a turn-buckle losa soV as to permit obtaining a relatively accurate amount of several ranges of tilting movement for the trays 25.

- To'provide support and guidance rorthegpans offood stu as they are discharged from the load supporting surfaces of the trays, provide a deilectorV chute H5, located immediately adjacent the unloading conveyer and extending at least the entire width of the trays 25. The de- Y flector chute includes an inclined portion ||6 disposed in a plane substantially coincident with the plane of the load supporting surface of the tray in its tilted positioncas seen in Figure 15 ofthe drawings. Thu-s vthe pans of food stuff as theyare discharged from the trays are supported and guided until they are lodged upon the upper run of the unloading conveyer from whence they kare conveyed and discharged ekteriorly of the oven. Y

The baking conveyer is preferably intermittently operated in timed relation to the unloading conveyer, so that when the baking conveyer is arrested, the unloading conveyer is likewise arrested, and wh'en the baking conveyer is oper-` ating, the unloading conveyer is operating. In this connection it should be understood that the dumping mechanism is also'connected by suitable and unloading conveyers may be performed autol maticallyV by suitable timing means or may be.

merely arrested automatically' and started manually. i

A By virtue of the construction described, the

operator is free to devote all of lhis time to loading Vof the food stuffs onto the baking conveyer, and generally speaking, no thought need be given to the task of unloading, which action is done automatically by the dumping mechanism andl the unloading conveyer.

There is a possibility of jamming of the pans of baked food stuffs on the unloading conveyer,

such as might occur by backing up of the pans of food stuff thereon by reason of not being permitted to freely discharge at the unloading end. When this occurs, th'e pans of food stul may jam immediately below the loading opening l2, and

'the jamming of the pans might become a serious menace if the conveyers and the dumping mech- -anis'm continue to operate, because the pans of 'food stuff will continue to be discharged from the trays and will tend to move transversely of th'e unloading conveyer. To assist in overcoming Vthis condition, Iprovide a safety door |20, hinged- V-ly mounted at its lower end at 172| in an openingA l|22, in the front wall of theloven, below the'load- Y ing opening I2, in'registration with the upper run of the unloading conveyer, as may be clearly seen in Figures 1 and '7 of the drawings.

To insure supporting the safety door |20 in Vupright position, I provide aconnection includl ing connecting rods and turn-buckle as indicated generally at |25, which' in turn are connected by Va light coil spring |26 to part. ofthe framing structure 61 of the unloading conveyer. In the event ofgjammng of the trays of food stuffs/on .decanen theiupperrunroii the unloading conveyenythepans willrtend'ftotabuteeaclr other'in. a. transverse directiori-Y with respectlto the:y unioadingrconveyer;

whichwill :be caused to: swingA downwardlyrto.- the dottedflineposition; in Figure, 7, which will relieve the-jamming ,conditionrto some: extent'. and.. will also direct;` the, attention of they :operator to the jammedscondition, who th'enl/will takeimmediate steps tofalleviatev the-condition.

Whenthe safety. vdoorfis inthe dottedl-linefposition: seen 1in Figure'r 1, itis, possible that some-.of` thel pans mightI even-be.moved,4 outward-ly` upon the 4uppersuriace Iof the 'door inesuchyposition..l In the event or the: pans, asr-dischargedr-fromr the trays, tending to pile one upon the other, 1provideran auxiliary-safetydoor |728 located immediately above.. the door 'E20-,as seenrin Fig-uref 'l oithedrawings. -As maybe seen in Figure: 'l of the. drawingssthis auxiliary door is:4 of `generally trapezodial Ishape .andL is A hingedly': conneotedi at itsr upper rear edgef as, indicated at |29, to apart ot. they orenv front-Wall; in the form of# a sill or shelf ystructure I 311-,` wh'ich definesthebottomf of the: loading opening l 2 incsad. Afrontwall of;y the oven.`

.-In. the eventv that. the;` 'pile-upf ofrthef pans` of baked food stuff ,become substantial, `the-pans mayy also: abut against: the.: auxiliary door/t28- and cause-itfto swing upwardlyto-.thefdottedfline position. seenI in Figure 10,l which: wille tondi to further relieve the-jammed condition and permitsome 3f-fthe ypans to-be discharged through'V the opening formed-:When the doors L20-and lIYZll-aieinlopen position; t

Although I have herein 4shown an'ddescribed certain preferred-f embodiments of myinvention, manifestly-1 it is capabley of-xrnodiiication and'r -rearrangementV of parts-Without; departing fromfthe spi-ritand` scope thereof. I do not, therefore; wish to beunderstood' as limitingthis invention tothe precise` forms hereinfdisclosed, except as; I may be solimitecl.V by the appended claims.

iiclaini:

l.; Aa baking: ovenf having: ai baking chamber; an endless;` horizontally traveling conveyor in rsaid chamber; andziin'cluding: aseries;` OfspaCed-apart, pivote-ily mounted trays for supporting; pansI of foodf. stuifronea end ofi said' conveyor Lbeingndisposed: adiacenti a. Aloading opening Vinllthe front Wall; of 'the' oven, an: endlessunloading; conveyor extending transversely of the tray -conveyer and disposedlfbelow theflatter andl adjacent the'.- front endvot' theloven andfhaxzingonez end extending through; a1 sidawallioff `saidE oven; means for-'tilting thelatrays` on the lower run oi'ithe4 tray conveyer for." discharging the pans of: *food* 'stuff ontozlthe upper run oi'tl'le'Y unloading conveyor; ai normally closed-v safety' r door'v provided 'in-z the front '.Wallhv of the oven;.-be1ow'said loadingV opening, andiinzregis'- tration-withsthe upper run'. of theliunloadingA conyveyer; and. spring: means for yieldingly maintaining-*saldi doorrin closed position: -thetension of sai'd'fsprizigy means-,being relatively: light; whereby said-f. door mayv be moved. tofopen-positiorr, against the reactioniof: said` spring means; when Vforcibly abutted. byspans: of foodstuff jamming om the upper of the unloading conveyor;

2'..1A baking oven having a-baking:chambe1,:an endless;v horizontally traveling, conveyor: inf.: said. chamber and including a series of spacedaapart, pivotally mounted. trays for supporting pans of food stuff, one end of said conveyer being disposed adjacent a loading opening in the front wall of th'e oven, an endless unloading conveyer extendingl transversely .of the., tray=conveyer and disposed .belowthe. latter v and.l adjacent the Vfront endgloflfthe oven andI having one', end extending through a, sidewall 'of said oven, means for tilting.

5 the-trays ontheilower run ofthe tray conveyer for-:discharging theI pans .of food stuff onto theA upperrunfof .the unloading conreyer,l a normally closed.. safety door provided in'. the front wall of the ovengib'el'owsaid'loadingT opening. and in l registration with Athe upper runv ofy the. unloading conveyor, saidsafety door. beinghingedly mounted at.y its', lower end; and: light,l tension. spring means fonho1ding1-s'aid' door in. uprighty closedA position, whereby forcible abutment of saidr door by pans l of food. stl" jamming .oni the upper runt. ofgthe unloading, conveyerrcauses saidV door to move out of:- .uprightI lstaliilil'edposition,- overcoming the force olsaid, spring .means, and.' assuming. an

openpositionl go l ,3.o A; `bakingoven-having.y a bakingv chamber, an endless, horizontally traveling conveyer in said chamber andV including aseriesof.A spaced-apart, pivotally mounted. trays' for supporting pans. of food stuff; one end. ofi said` conveyor being disposedadjacenta, loading -opening-` inl-the iront Wall. of the ovenan endless .unloading conveyer extending, transversely of.V the Ltray conveyor `and disposed. below ythelatterv and adjacent.f the front end. of! the. oven and having one endextend'ing throughlaside-wallof'said. oven,.means for tilt,-`

' ngr-the-trayson' the Alower runof they tray conveyer. for: discharging. the; pans. ofe vfood stuionto the upper run 'oilu the-unloading conveyor, a-normally.V upright safety. door. in the/front Wa-ll. of

the oven; below said loading. opening, registrationwiththe-upper run of, thefunloading conveyer, saidL door.. being', .hingedly mounted on a horizontal axis at. its. lowerlend, spring means normally holding'said door in: uprightclosed posi- 40 tion,V andan auxiliary safety `door .inthe-front wall of`` oven, hingedly mountedzatsitsfupper end and. disposedimmediately above. said upright door,v saidldoors serving .toA :jointly constitutea closure fon a single opening. in said front Wall 45 orthemren.I v l ,y

4f. A l baking.I oven. having.L a. baking` chamber, ari-endless:` horizontally l#traveling conveyor in saidnchamber and including aseries of,w spacedapart,. pivotally mounted' 4trays for supporting 59 pansof food stuff; one end of-said conveyor being disposedladjacenta loading openinglinthe-front wall of the oven, an:endlessunloading-conveyor extendinatransversely ofcthettray conveyor and disposed below. 'the.1atterand adjacent theiront end or the roven: and Vhaving one ends extending through a-sidefvwall ofsaid oven, means` for tilting the `vtrays. onothe-lower runl of ,the trayy conveyor fondischarging the pans of lfood stul. onto the-upper rulrl ortho-unloadingfconveyer, and

`00 heat transfer meanslooated adjacent-*the bottom oi'the baking chamber and. including aA header adjacent-each end of said chamber, one. of. said headers Abeing disposed: between7 the upper and lower runs of the tunloading.- conveyer at-the front t endof the chamber. y

' 5.- an` endless: tray oonveyer, a pair of aligned, aXiaIIMspaced-apart vdriving `sprocket wheels, separate,5 spaced. apartstrandsof. endless chain trained-around said zWheels; at one end,

17 guida-means for Athe:opposite ends of the; chains, track-means; for supportingl the upper and; lower runs: off. rthe.V chainsf: a plurality off AmaterialY v slipporting trays pivotally supported at opposite ends on said strands of chain, said pivot connection i comprising trunnions on each tray located in transverse alignrrient.with` each other-,at onev side of the ^centerof the length of said tray, an auxiliary strand of -endless chain disposed parallel and, adjacent to one of theV aforemen-i tioned chains, means for guiding said auxiliary strand of chain for movement in a predetermined path, separate rigid controlmembers for each tray, yjournaled on the trunnionfon the side adjacent the auxiliary strandrof chain, each of said members including a paireof` arms extending in the same direction toward the farthest edge ofV the tray, on opposite sides of the adjacent driving strand of chain, the outer arm having its end opposite the trunnion pivotally connected to the auxiliaryV strand ofchain on an axis parallel to the trunnionA axis, andmeans on the vadjacent end lof the tray, located at the side voi the center vopposite the pivot axis thereof, adapted to enthe same direction toward the farthest edge of the tray, on opposite sides of the adjacent driv` ing strand of chain, the youter arm lhaving its end oppositev the trunnionV pivotally connected to the auxiliary strand of chain on an axis parallel to the trunnion axis, and means on the adjacent end of the tray, located at the'side of thecenter opposite the pivot axis thereof, adapted toenf gage the upper surface of the inner arm oi said control Vmember for supporting the tray 'in a substantially horizontal position, said last inentioned means being adjustable in vertical direc- Y tion and constituting a stop engageable with said gage the inner arm ofsaid control member for supporting the tray in a substantially horizontal position. Y Y.

6,1[nanV endless tray conveyer, a pair of aligned, axially spaced apart driving sprocket wheels, separate, spaced apart strands vofendless chain trained around said, wheels at one end,

Vguide means for the' opposite ends of the chains,

track means for supporting the upper and lower runsof the chains, a plurality of material supporting trays pivotally supported at opposite ends onrsaid strands oi'fchain, saidfpivot connection comprising trunnions'onA eachV tray. located in transverse alignment with each other at one side control member to preclude tilting ofthe tray downwardly at the side opposite the pivot axis thereof.V j v 8. In an endless tray conveyer,r a pair f of aligned, axially spaced-apart driving sprocket wheels, separate, spaced-apart strands ofendless chain trained around said wheels at one end,

Y guide means for the opposite ends of the chains,

of the center ofY the length of said tray, an`

auxiliary strand of endless chain disposed parallel anderadjacent Nto one of "the aforementioned chains, means for guiding said auxiliary strand of chain formovement in a predetermined-path,

separate rigid control members for each tray, journaled on the trunnion on the side adjacent the auxiliary strand oi chain, each of said members including a` pairof arms extending in the same direction toward the farthest ,edge orv the trayon Yopposite sides of the adjacent drivingl strand of chain, the vouter armhaving nits end opposite the trunnion pivotally connected to the auxiliary strand of'. chainon an axis parallel -to Y'the'trunnion axis, and means on the adjacent fiend of the tray, located at the sidefof the center opposite the pivot axisA thereof, adapted to en- ,f

gage the upperY surface of the inner arm of said control member forsupporting the tray in va substantially horizontal position.

track means for supporting the upper and lower runs of the chains, a plurality of material supporting trays pivotally supported at opposite ends on said strands Yof chain, said pivot, connection comprisingy trunnions on each tray locatedfin transverse alignment with eachother at one side e of the center of the length oi said tray, an auxiliary strand 'of endless chain disposed parallel and adjacent to one of theY aforementioned chains, means for guiding said auxiliary strand of chain for movement in a predetermined path,

separate rigid control Vmembers for each tray,V

journaledvon the trunnion'on the side adjacent the auxiliary strand of chain, each of said mem# bers including a pair of arms extending in the same direction toward thefarthestedge of the tray, on opposite sides of the adjacent driving strand of chain, the outera'rm having its end 4o opposite the rtrunnion pivotally connected to the auxiliary strand of chain on an axis parallel to the trunnion axis,4 and means on the adjacent end of the tray, located at the 'side of the center opposite the pivot axis thereof, adaptedto lengage the inner arm of said control member for supporting the tray in asubstantially horizontal poe sition, said armsoi each' control member being 7. In an endless tray conveyer,;a pair of4 aligned, axially spaced apart driving sprocket wheels, separate, spaced apartY strands of endless chain ,trainedY around said wheels at one end, guide means Vfor the Aopposite ends yof the chains, track means for Asupporting the upper and lower runs of the chains, a plurality ofv material sup porting trays pivotally supported at opposite ends on said strands of vchain, said pivot connection comprising trunnions on each tray located in transverse alignment witheach other Vat one side of the A4center of the length oi' said (tray,-i an auxiliary strand of endless chain disposed4 Vparallel and adjacent'to one of the aforementioned chains, means for guiding said auxiliary strandl of chain for movement in a predetermined path, separate rigid control members for each tray,v journaled on the trunnion on the side adjacent the Yauxiliary strand of chain, each of said members including a pair of'armsextendng in vrality of spaced apart material supporting trays pivotally supported at opposite ends on said' strandsof chain, said guide means forY each strand of chain comprising a curved downwardly extending section merging with the track for the lower lrun of the chain, a curved upwardly ex- Y tending section, located in longitudinally onset relation to the other section, merging with the track for the upper run of the chain, and a straight inclined section joining said two curved sections. ,Y Y

" JOHN v. COOK;V 

